Over the past year I have been "experimenting" with various one-dimensional tissue models of dysmorphogenesis. The basic underlying assumptions of these models are two-fold: 1) fundamental laws of nature determine the cause of development and define the scale of values by which it occurs; b) the effects of a chance occurrence can change the configuration of development, within the context of natural law, and set it running in a totally new direction. Thus abnormal development could occur in the absence of genetic and/or environmental perturbation. Thus far, complex variations of the so-called "statistical bead game" appear to hold the most promise in developing the most testable model. The objective for the coming year is to further develop the model using computer simulation techniques. Other studies in the coming year include: a) genetic analysis of cleft lip data from Shanghai, China in collaboration with Dr. Dan-Ning Hu of the Shanghai Society of Genetics - these studies will employ complex segregation analysis as well as test of the polygenic model; b) study of the effects of chorion type on variation in body surface area in twins at birth, 1 yr. and 7 yrs., as well as the effect of genetic variation.